ORGANIC CHEMISTRY NOTES
Complete A+ Grade Study Guide | Semester 1 & 2
Written by a 4.0 GPA Student | All Major Topics | Mechanisms, Tables, Practice Problems & Exam Tips
,TABLE OF CONTENTS
SEMESTER 1
• Chapter 1: Bonding & Molecular Structure
• Chapter 2: Acids & Bases
• Chapter 3: Alkanes & Cycloalkanes
• Chapter 4: Stereochemistry
• Chapter 5: Substitution Reactions (SN1 & SN2)
• Chapter 6: Elimination Reactions (E1 & E2)
• Chapter 7: Alkenes
• Chapter 8: Alkynes
• Chapter 9: Alcohols & Ethers
• Chapter 10: Spectroscopy (IR, NMR, Mass Spec)
SEMESTER 2
• Chapter 11: Conjugated Systems & Diels-Alder
• Chapter 12: Aromatic Compounds & Aromaticity
• Chapter 13: Electrophilic Aromatic Substitution
• Chapter 14: Aldehydes & Ketones
• Chapter 15: Carboxylic Acids & Derivatives
• Chapter 16: Enols & Enolates
• Chapter 17: Amines
• Chapter 18: Carbohydrates
• Chapter 19: Amino Acids & Proteins
• Chapter 20: Lipids
, SEMESTER 1 Chapters 1 – 10
CHAPTER 1 BONDING & MOLECULAR STRUCTURE
KEY CONCEPTS
Atomic Orbitals
• Electrons exist in orbitals around the nucleus
• Types: s (spherical), p (dumbbell-shaped), d, f
• Each orbital holds a maximum of 2 electrons
Key Vocabulary
• Electronegativity: Ability of an atom to attract electrons in a bond. Order: F > O > N > Cl > Br > C >
H
• Formal Charge = (Valence e⁻) − (Non-bonding e⁻) − ½(Bonding e⁻)
• Resonance: When one Lewis structure cannot represent a molecule. Only ELECTRONS move,
never atoms.
• Hybridization: Mixing of atomic orbitals to form new hybrid orbitals.
HYBRIDIZATION TABLE
Hybridization Geometry Bond Angle Example Orbitals Mixed
sp³ Tetrahedral 109.5° CH₄, water 1s + 3p
sp² Trigonal Planar 120° Ethene (C₂H₄) 1s + 2p
sp Linear 180° Ethyne (C₂H₂) 1s + 1p
💡 sp³ carbon = 4 single bonds | sp² = 1 double bond (1 pi) | sp = triple bond (2 pi)
SIGMA vs PI BONDS
Feature Sigma (σ) Bond Pi (π) Bond
Overlap Head-to-head Side-to-side
Rotation Free rotation NO free rotation
Strength Stronger Weaker
First bond? Yes (always) No (2nd/3rd bond only)
💡 Every bond has 1 sigma. Double bond = 1σ + 1π. Triple bond = 1σ + 2π.
, INTERMOLECULAR FORCES
Force Strength Description Example
Ion-Ion Strongest Between opposite ions NaCl
Hydrogen Bonding Strong N-H, O-H, F-H with lone pair Water, alcohols
Dipole-Dipole Moderate Between polar molecules Acetone
London Dispersion Weakest All molecules, temporary Alkanes
dipoles
💡 Boiling point increases with stronger IMFs. Alcohols have much higher BPs than alkanes of
similar MW.
COMMON MISTAKES
❌ Moving atoms in resonance structures → Only ELECTRONS move. Atoms NEVER move.
❌ Confusing sigma and pi bonds → Double bond = 1 sigma + 1 pi. First bond is ALWAYS sigma.
❌ Thinking all sp³ atoms are carbon → N in amines, O in water can also be sp³.